Doing vectored buf-select read with 0 iovec passed is meaningless and utterly broken, forbid it.

Cc: stable@vger.kernel.org # 5.7+ Signed-off-by: Pavel Begunkov asml.silence@gmail.com --- fs/io_uring.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index b74957856e68..f3690dfdd564 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3125,9 +3125,7 @@ static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov, iov[0].iov_len = kbuf->len; return 0; } - if (!req->rw.len) - return 0; - else if (req->rw.len > 1) + if (req->rw.len != 1) return -EINVAL;

#ifdef CONFIG_COMPAT